Perfectly Inelastic Collision

Definition

A perfectly inelastic collision is a type of collision where the colliding objects stick together after impact, resulting in a single object with a combined mass and a shared velocity. In this type of collision, the total momentum of the system is conserved, but the kinetic energy is not.

5 Must Know Facts For Your Next Test

1. In a perfectly inelastic collision, the final velocity of the combined objects is the same, regardless of their initial velocities.
2. The total momentum of the system is conserved in a perfectly inelastic collision, but the total kinetic energy is not.
3. Perfectly inelastic collisions result in a loss of kinetic energy, which is converted into other forms of energy, such as heat or sound.
4. Perfectly inelastic collisions are often used to measure the impulse of a collision, as the change in momentum can be easily calculated.
5. The coefficient of restitution, which describes the elasticity of a collision, is zero for a perfectly inelastic collision.

Review Questions

• Explain how a perfectly inelastic collision differs from an elastic collision in terms of the conservation of momentum and kinetic energy.
  • In a perfectly inelastic collision, the colliding objects stick together after impact, resulting in a single object with a combined mass and shared velocity. The total momentum of the system is conserved, but the total kinetic energy is not. This is in contrast to an elastic collision, where the colliding objects separate after impact, and both momentum and kinetic energy are conserved.
• Describe how the concept of impulse is related to perfectly inelastic collisions.
  • Perfectly inelastic collisions are often used to measure the impulse of a collision, as the change in momentum can be easily calculated. Impulse is the product of the force applied and the time over which it is applied, and it is equal to the change in momentum of an object. In a perfectly inelastic collision, the change in momentum can be directly observed, as the colliding objects stick together and move at a shared velocity after the impact.
• Analyze the relationship between the coefficient of restitution and the type of collision, and explain how this relates to a perfectly inelastic collision.
  • The coefficient of restitution is a measure of the elasticity of a collision, with a value of 1 indicating a perfectly elastic collision and a value of 0 indicating a perfectly inelastic collision. In a perfectly inelastic collision, the coefficient of restitution is zero, meaning that the colliding objects stick together and do not separate after impact. This results in a loss of kinetic energy, as some of the energy is converted into other forms, such as heat or sound. The lack of separation between the objects and the conservation of momentum are key characteristics of a perfectly inelastic collision.

Related terms

Impulse: Impulse is the product of the force applied and the time over which it is applied, which is equal to the change in momentum of an object.

Conservation of Linear Momentum: The principle that the total momentum of a closed system is conserved, meaning the total momentum before a collision is equal to the total momentum after the collision.

Inelastic Collision: A collision in which the colliding objects do not separate after impact, and some of the kinetic energy is converted to other forms of energy, such as heat or sound.